Coffee's Ubiquity & Availability
Coffee is one of the most popular drinks in America. A 2015 Gallup poll found that nearly two-thirds (64%) of Americans drink at least one cup of coffee per day. See http://www.gallup.com/poll/184388/americans-coffee-consumption-steady-few-cut-back.aspx. More telling, the same poll found that the average coffee drinker in America drinks nearly three full cups of coffee each and every day. Id.
Given coffee's wild popularity across the country, it is not surprising that coffee drinkers have more options for obtaining a cup of coffee than ever before. Today, coffee drinkers can purchase a cup of coffee at name-brand commercial coffee shops, like Starbucks and Dunkin Donuts; gas stations; street vendors; at fast food locations, such as McDonald's (as well as at almost any food serving establishment); and at numerous other locations (all locations at which a coffee drinker may purchase coffee outside of their home are collectively referred to hereafter as “coffee shops”). And research suggests that coffee drinkers indeed swarm coffee shops. Trade magazines report that the average Starbucks serves over 500 customers each day and Dunkin Donuts reports that is sells nearly 2 billion cups of coffee in America each year. http://www.businessinsider.com/how-many-customers-starbucks-will-have-2013-10; https://news.dunkindonuts.com/news/brand-keys-names-dunkin-donuts.
Despite the ubiquity of coffee shops, the overwhelming majority of American coffee drinkers still make their coffee at home. See, e.g., https://www.aol.com/2011/01/25/savings-experiment-the-perks-of-brewing-versus-buying-coffee/. Making coffee at home offers numerous advantages. The most notable advantage is cost: making coffee at home is drastically cheaper than buying it at coffee shops. The average cost of a cup of coffee that is purchased on-the-go ranges between $2-$5. The average cup of coffee brewed at home, however, costs on average only 16 to 22 cents depending on how much you spend per pound to buy the coffee. For example, at $8 per pound (a common price for many types of coffee in typical US grocery stores), the average 10 cup per day user spends $0.20 per cup. Not surprisingly, numerous publications that advise consumers about how to increase their savings counsel consumers to make coffee at home rather than paying the comparatively high prices charged by coffee shops.
But there is a significant drawback that at-home coffee drinkers must face: poor quality and taste (this can also be a significant problem at coffee shops). Many people believe that the beans that a person uses will dictate the quality and taste of coffee brewed at home. But while bean quality is certainly a factor that impacts taste, the factor that most overwhelmingly influences the quality and taste of coffee is the method of brewing.
The Science of Making Coffee
Humans have been brewing and drinking coffee for more than 500 years. But over that time, the science of making coffee has not changed significantly. When coffee is “brewed,” technically what the user is doing is using hot water to extract natural oil from coffee beans. This oil infuses with the hot water used to extract the oil, and the resultant oil-water mixture is what we refer to as “brewed coffee.” (Although “cold brewing” has become popular in recent years, cold brewing coffee involves a wholly different brewing process than is used for brewing hot coffee).
As explained further below, the invention disclosed herein utilizes a process known as “agitated infusion” that is not utilized by any coffee brewing system that is currently available (other than US application No., to which this application claims priority). Agitated infusion is the process of immersing coffee grounds in water that is at or about tap temperature, gradually heating the water to approximately boiling, and agitating the grounds within the water while it is heated to approximately boiling. This gradual raising of the water temperature to near 212 degrees, combined with agitation of the grounds that are fully immersed in the gradually heating water (as explained herein), achieves the maximum extraction of oil from the coffee grounds, which results in two significant advantages: (i) the brewed coffee that is produced is richer in flavor: and (ii) because the infusion process extracts significantly more oil from the coffee grounds than other coffee brewing processes, the user is able to achieve a richer tasting brewed coffee using less coffee grounds, which is more efficient and results in the user saving significant amounts of money. Any variation from the agitation infusion method, such as using water heated to a lower temperature or failing to utilize the gradual heating process and agitation (or any other variation), will result in the brewing process being unable to extract the very high percentage of oil from the grounds that can be extracted using agitated infusion. Failing to fully submerge the grounds in the water during the agitating and heating process, as provided during agitated infusion, will significantly diminish the quality of the brewed coffee.
The industry's most relevant and widely utilized methods of brewing coffee, none of which utilize the agitation infusion process as present invention does, are discussed below.
Turkish Coffee
Turkish coffee is among the oldest methods of brewing coffee and the process of making Turkish coffee is well known. For a good example of the prior art's discussion of Turkish coffee, see WO2007116350 A1 (Suleyman, et al). In short, to make Turkish coffee, the user places water into a carafe (or other receptacle) and places the carafe over heat (such as the flame of a stove or, in past times, the flame of a fire). Then the user heats the water to a medium-high temperature. Once the water reaches that medium-high temperature, the user adds finely ground coffee to the carafe. The user then stirs the coffee within the carafe and allows the water with the coffee therein to continue to heat; this process extracts the oil from the coffee so that the oil begins to mix with the water, which forms brewed coffee. Once the coffee grounds begin to sink, the user stirs the coffee-water mixture again; this stirring extracts even more oil from the coffee grounds and creates a consistent brewed coffee. As the user stirs, the coffee-water mixture should begin to foam up. Once the coffee-water mixture begins to foam, the user stops stirring and removes the coffee-water mixture from heat. After a short time (approximately 30 seconds), the coffee grounds will settle to the bottom of the carafe and the brewed coffee mixture can be carefully poured into cups and served.
French Press
Among widely utilized coffee makers, French Press systems are generally considered to produce the best tasting coffee. In nearly every survey taken of coffee drinkers, the French Press is thought to be the best brewing method. Not surprisingly, many exclusive restaurants use only the French Press method.
A typical example of the French Press process of brewing coffee is disclosed in U.S. Pat. No. 6,422,133 B1 to Brady. Like making Turkish coffee, a French Press system works by immersing ground coffee (freshly ground coffee is preferred, but not necessary) directly into water—but the remainder of the process is different. In a French Press system, the user pours coffee grounds into the empty French Press carafe. After doing so, the user adds water that has been heated to approximately 212 degrees. The hot water will begin extracting oil from the coffee grounds to form brewed coffee. At this point, some French Press users will stir the grounds within the water in an effort to extract additional oil from the grounds, others do not stir. Whether the grounds are stirred or not, after the water is added the user must wait 3-6 minutes. During this time, the hot water will continue extracting oil from the coffee grounds to create a more robust brewed coffee, but the temperature of the water will decrease quickly and the process of extracting oil will be weakened as the temperature falls. After these 3-6 minutes pass, the user slowly lowers the French Press “plunger” from the top of the carafe to bottom. The head of the plunger is usually designed similar to a “screen,” which permits the brewed coffee to pass through while forcing the now used coffee grounds to the bottom of the carafe. Once the brewed coffee is separated from the grounds, the user can pour the coffee out of the carafe and into a mug.
Pour Over
The “pour over” method of brewing coffee is often also lauded as producing high quality coffee. Most often associated with the brand Chemex®, the pour over method involves the steps of heating water to boiling, placing ground coffee within a filter and positioning the filer above a receptacle capable of storing brewed coffee, removing the boiling water from the heat source and pouring it over the coffee grounds so that the water flows through the grounds and into the receptacle. Most pour over users utilize a specific method of pouring the water over the coffee, which may include multiple pouring steps, in an effort to extract the maximum amount of oil from the grounds.
Drip Brewing Systems
There is no doubt that the most utilized coffee brewing system today is the “drip”; drip coffee makers have been a mainstay in the majority of American homes for decades. The standard drip system is described in U.S. Pat. No. 5,001,969 to Moore, et al and brews coffee by spraying hot water over coffee grounds that are held in a filtered basket situated above a carafe. The sprayed hot water trickles downward through the grounds and as it does so the hot water extracts and mixes with the oil from the coffee grounds. There is an opening in the bottom of the basket that houses the filtered coffee grounds. When the water trickling downward through the basket reaches the bottom (and by this time has extracted and mixed with oil from the coffee grounds), the now-formed brewed coffee exits the basket through a hole in the basket's bottom and empties (i.e., drips) into a carafe (or other storage receptacle) that stores the coffee until the user transfers it into a mug for drinking. The storage receptacle usually includes a means for keeping the receptacle and brewed coffee heated. For standard drip systems that utilize a carafe for storing the coffee, the carafe often rests atop a hot plate that keeps the brewed coffee warm.
There are many variations of drip systems designed to suit user preferences and to enhance the quality of the coffee that drip makers brew. For example, U.S. Pat. No. 5,001,969 discloses a drip system that includes timers to permit and regulate automatic brewing cycles that allow the system to brew coffee even when the user is not present. U.S. Pat. No. 4,406,217 to Oota discloses a drip system that includes a mill to grind coffee immediately prior to brewing, the idea being that freshly ground coffee will produce more flavorful coffee. Other variations of drip systems maintain a reservoir of hot water that can be immediately sprayed over the coffee grounds so that the user does not have to wait for water to be heated or an internal “tank” where the brewed coffee is stored, as opposed to a carafe, and the user opens a spigot (or performs a similar function) and the coffee-water mixture drains from the “tank” into the user's mug. This saves the user the trouble of washing a carafe. Despite how drip system may be varied or the “bells and whistles” that may be included for user preference, the majority of drip systems still employ the same process to brew coffee: spraying heated water over coffee grounds, with the water eventually draining into a receptacle from which the coffee is then transferred to the user's mug.
There are, however, a minority one drip system that utilizes a form agitation to brew higher quality coffee. For example, U.S. Pat. No. 6,532,862 to Mork, et al discloses a drip system that utilizes a spinning basket to create centrifugal forces to more thoroughly infuse the coffee grounds with water. Mork also notes additional prior art that utilizes centrifugal forces to more thoroughly infuse the coffee grounds, such as U.S. Pat. No. 5,265,617 to Gilbert and U.S. Pat. No. 1,602,632 to Zorn. Cuisinart has also recently release its DCB-10 Automatic Cold Brewing System, which uses agitation to “cold brew” coffee at a pace that, the company claims, can produce quality cold brew coffee in less than one hour. Because cold brewing uses water that is not heated, the process usually requires far longer to brew coffee than is required to brew hot coffee because cooler water less able to extract oil from coffee than hot water. For example, many cold brew coffees are brewed for several hours or even overnight. The Cuisinart DCB-10 system claims that, through its agitation process, it can brew quality cold brew coffee in less than one hour. As explained further below, even these systems that utilize agitation and infusion do so in a manner unlike and inferior to the invention disclosed herein.
Single-Cup Coffee Brewers
Single-cup coffee makers, such as the Keurig brewing system that is covered by numerous US patents, including U.S. Pat. Nos. 7,398,726; 7,165,488; 7,347,138; D513,572; 7,377,162; D544,299; 7,360,418; 7,513,192; 8,151,694, have over the last several years become extremely popular because of their convenience and speed. Rather than requiring the user to place coffee grounds in a basket or directly into water within a carafe, single-cup coffee makers use coffee “pods” (these coffee pods are commonly referred to as “K-cups”). The coffee pods are a single-use, premeasured and prepackaged amount of coffee grounds that may be used to brew a single cup of coffee (as opposed to multiple cups of coffee, which can be brewed using the Turkish, French Press, and drip systems discussed above). Single-cup coffee makers heat water to approximately 192 degrees before it inundates the grounds. To initiate the brewing process, a user opens the system's coffee pod chamber and places a pod into the chamber. Next, the user closes the chamber. The chamber is designed so that by closing the chamber with a coffee pod therein, the chamber's structure will pierce the upper portion of the coffee pod from above and pierce the lower portion of the coffee pod from below.
Once the chamber is closed, the user can begin the coffee brewing process, which is usually done simply by pressing a “start” button. This causes the system to pump heated water into the chamber. When the water enters the chamber, it enters the coffee pod via the opening in the pod's upper portion that was created when the chamber closed. Once the water enters the pod, it inundates the coffee grounds contained therein, which extracts and mixes with oil from the grounds to create brewed coffee. The force of water being pumped into the chamber, as well as gravity, force the brewed coffee to flow out of the opening in the bottom of the pod, which is situated above an opening in the bottom of the chamber, and the brewed coffee then flows out of the machine and into the user's mug, which is situated below the opening in the bottom of the chamber.
Percolators
The modern iteration of a percolator coffee maker was patented in 1889 by an Illinois farmer named Hanson Goodrich, see U.S. Pat. No. 408,707 (other iterations of percolators are thought to have been utilized as long ago as 1810). In modern percolators (hereafter “percolators”), which have changed little if at all since Hanson Goodrich, the entire brewing process occurs within a carafe; the design and process is as follows:                The carafe must be fabricated using material that can withstand and transfer high levels of heat; metal is generally preferred;        The carafe has a removable lid;        Toward the top of the inside of the carafe, but not at the top of the carafe, there is a chamber (often made from metal mesh);        The chamber is typically donut-shaped, so that there is an opening in the middle;        Tubing (like a pipe) extends from the opening in the middle of the chamber, downward, toward the bottom of the carafe, but the tubing does not reach or contact the bottom of the carafe;        A user pours a desired amount of water into the carafe;        The user places a desired amount of coffee grounds in the chamber (there are commercially available “packets” of coffee grounds for use in percolators; the packets are typically made of the same material as coffee filters, contain a premeasured amount of coffee grounds, and are often donut-shaped, like the chamber, which can be significant, as explained below);        The user then places the carafe over a heat source, which today is generally the flame (or electric burner) of a kitchen stove;        The user adjusts the heat so that the water within the carafe rises to boiling or approximately boiling;        As the temperature of the water approaches boiling, the water (some of which will transition to a gaseous or semi-gaseous state) travels up the tubing from the bottom of the carafe to the top region of the carafe above the chamber that holds the coffee grounds;        When the water reaches the top region of the carafe, it falls downward due to gravity and any water that has transitioned to a gaseous or semi-gaseous state condenses in the carafe's top region, returning to a liquid state, and falls downward due to gravity;        When the water falls downward, it falls atop the coffee grounds or the packet of coffee grounds that is held in the chamber;        The falling water then trickles through the grounds, extracting oil therefrom;        When the water (which has mixed with the oil extracted from the grounds) reaches the bottom of the chamber, it falls through the chamber's mesh (or otherwise porous bottom), and mixes with the rest of the water that is in the carafe's bottom region.        
As long as the heat remains sufficiently high, the water in the percolator constantly cycles from the bottom of the chamber, up the tubing, and downward through the grounds. The more cycles that the user allows, the more robust the coffee will be.
When the user has permitted the percolator to cycle for a desired amount of time, the user removes the carafe from the heat source. A short period of time after the user has removed the carafe from the heat source, the percolator will stop cycling. The user then pours the coffee that is now stored in the bottom of the carafe into a coffee cup and enjoys the coffee.
Shortcomings of Currently Available Coffee Brewing Systems
Unfortunately for consumers, all of the coffee brewing systems currently available are plagued by significant shortcomings that impair the quality of the coffee they produce or make the systems inconvenient for consumers and relatively expensive. A non-exhaustive discussion of significant shortcomings of each system, many of which the present invention seeks to remedy, are explained below.
Turkish Coffee Shortcomings
For most consumers today, the most significant problem of making Turkish coffee is the inconvenience of the brewing process. It is no coincidence that single-cup brewers have exploded in popularity; in today's on-the-go world, putting a pod into the chamber and pressing start is the easiest way to make coffee. In contrast, Turkish coffee requires multiple steps that are comparatively laborious. The user must heat water and then deposit coffee grounds therein. Then the user must continue heating. Not only does this require work from the user, it also requires vigilance. Unlike drip and single-cup systems, where once the brewing process begins the user can simply wait for the coffee to be ready drink, brewing Turkish coffee requires the user to watch over the process from start to finish. Many if not most Americans simply do not have the time in the morning to devote such vigilance to making coffee, as they are preparing for work; preparing children to go to school; assisting spouses with their morning preparations; or caring for pets—for many Americans, each morning involves a combination of these tasks.
Aside from inconvenience, Turkish coffee also inheres several systemic problems for consumers. For example, if the consumer is not vigilant in the water heating process the grounds can remain in boiling water for too long of a time resulting denatured coffee which can be very bitter Another potential problem is that consumers will pour the brewed coffee from the carafe before the coffee grounds have fully settled, which results in consumers drinking coffee grounds, which is undesirable. Still another problem is clean up. Once the brewing process is complete, the user is left with a carafe full of wet, used coffee grounds that must be discarded and the carafe must be cleaned before it may be used to make more coffee.
As far as taste, the principal problem with Turkish Coffee is that the water used to extra oil from the grounds is generally heated to a medium-hot temperature before the grounds are added or is heated for too long. As explained further, infra, an important aspect of the agitated infusion process disclosed herein is the gradual raising of water temperature while coffee grounds are immersed therein. By beginning the brewing process with water heated to a medium temperature (as opposed to the near boiling temperature water that many of the other brewing processes discussed herein utilize), Turkish coffee does, more than any other method of brewing coffee available to consumers to date, utilize the infusion process—but only to a relatively minor degree as compared to the present invention.
French Press Shortcomings
French Press systems suffer from the same convenience problems that plague Turkish coffee: the user must manually heat water, add grounds, and remain vigilant until the process is complete, and cleanup is inconvenient. In addition, most French press carafes are much smaller than drip system carafes. Because the size of the carafe is smaller, and the work and time involved to brew French Press coffee, if a person has house guests (or otherwise needs to make coffee for more than one or two people), a French press system will generally be undesirable. Also French Press coffee makers do not have heating elements to keep the brewed coffee hot.
French Press systems also fail to take advantage of the infusion process. As noted above, when a user pours preheated water into the French Press carafe, the water is already heated to approximately 200+ degrees. Although infusing the grounds in water heated to 200+ degrees will extract more oil than lower temperature coffee brewing methods (such as drip systems and single-cup systems, see infra), failing to employ the infusion process that involves gradually raising the water's temperature and constant agitation means French Press systems will not extract the maximum amount of oil from the grounds, which means the brewed coffee will not be as robust in flavor as it could be. In addition, the water used to brew coffee using a French Press begins to immediately cool once it is removed from the heat source, which further reduces the ability of French Press systems to extract maximum oil from the coffee grounds.
Pour Over Shortcomings
The pour over method suffers shortcomings inherent to both the Turkish method and French Press systems. For one, the user has to undergo the inconvenient process of separately heating water before coffee can be made. Second, the heated water begins to cool as soon as it is removed from the heat, reducing the pour over method's ability to extract oil from the grounds. In addition (and again like French Press), many pour over carafes hold a smaller volume of coffee and lack a heating element (although some pour over carafes are specifically designed so that they may be placed on top of a stove to keep the coffee warm, but this remains a far cry from the heating elements included in some systems, such as those included in many drips).
The pour over method also lacks true agitation. The coffee grounds merely sit stationary in the filter while water is poured over them. And even altering the pouring method does not result in true agitation or immersion.
Drip System Shortcomings
Most drip systems inheres a host of shortcomings. First, the water temperature of most standard drip coffee makers is heated no higher than 170 degrees before it is sprayed over the coffee grounds. This poses two problems. First, by merely preheating water to 170 degrees and spraying it over grounds, drip systems fail to in any way take advantage of the infusion process. Second, water that is heated to 170 degrees is not hot enough to extract anywhere close to the maximum amount of oil from the coffee. To extract the maximum amount of oil, the water temperature must reach approximately boiling. Further, the water begins to cool quickly after being sprayed on to the grounds, which further impairs the ability of most drip systems to extract oil from the grounds.
The second major problem with most drip coffee makers is the process by which they extract the coffee oil. To extract the maximum amount of oil, coffee grounds should be immersed in water and agitated. But most drip systems simply spray hot water on to grounds, which is referred to as “washing” the grounds. When grounds are merely washed in a drip system, the water sometimes only washes the grounds directly below or very close to the nozzle from which the water is sprayed (many drip coffee makers have numerous nozzles). As a result, there are instances when only a fraction of the coffee grounds are fully washed. This means that oil is extracted from only a fraction of the grounds and the coffee brewed therefrom is only a fraction as flavorful as it would be if all of the grounds were completely washed. Besides dampening the coffee's flavor, the inability of most drip systems to extract oil from all of the coffee grounds means that consumers are wasting large amounts of money on coffee grounds that are never actually used to brew coffee. For consumers that buy high quality beans, the day-in, day-out waste of “unused” grounds can equate to a significant amount of wasted income. So in sum, drip brewers force consumers to overspend to brew coffee that has a dampened flavor.
As noted above, a minority of drip systems incorporate a process by which centrifugal force circulates water through the grounds. While this may be an improvement over the spraying and washing method, it is still less effective at extracting oil than the agitation and infusion method disclosed herein. In addition, the centrifugal processes do not employ the gradual heating process disclosed herein; the water in those systems is heated prior to circulating through the grounds. See, e.g., U.S. Pat. No. 6,532,862 to Mork.
Single-Cup System Shortcomings
As noted above, single-cup brewing systems inundate the grounds in the pods with water that is preheated to 192 degrees. While water heated to 192 degree will extract more oil from the grounds than water heated to 178 degrees, 192 degrees is still below the ideal approximately boiling temperature. And like other methods of brewing coffee, because the water is pre-heated to 192 degrees before inundating the grounds, single-cup brewing systems fail to utilize the gradual heating that is involved in the infusion process.
And, of course, single-cup systems only brew a single cup of coffee at a time. While this is often convenient, if a person has house guests or needs to make coffee for many, reliance solely on a single-cup system can be inconvenient. Finally, single-cup systems are generally considered bad for the environment because their use generates millions of used plastic pods that must be discarded.
Percolator Shortcomings
Like the French Press and pour over, percolator systems require significantly more time, effort, and vigilance than most coffee drinkers are willing to expend. The heat employed to cause the water to rise through the tubing must be monitored, as must the length of time that the user allows the percolator to cycle, because permitting the water within the percolator to reach too high a heat or to heat for too long may result in the coffee oils breaking down, which results in poor taste. In addition, if a user does not use packets of coffee in the percolator, but instead adds coarse-ground coffee grounds directly to the chamber (which is commonly done), there is a high likelihood that some of the coffee grounds will fall through the openings in the chamber's bottom. This will ultimately result in the grounds being in the coffee when the user drinks it, which is undesirable
Percolators also fail to employ any aspect of agitated infusion. Like a drip system, water merely trickles down through and washes the grounds—it does not inundate the grounds. Further, there is no agitation; the grounds merely sit in the chamber while being washed.